Hydrogenation of hydrocarbons and apparatus therefor



Aug. 23, 1932. 1,872,839

HYDROGENATIQN oF HYDRocARBoNs AND APPARATUS THEREFOR F. T. SNYDER`Original Filed Deo. 16; 1925 Y L Y Patented Aug. 23, 1932warrencsrA'l'fESj PATENT. yerFiclE;

FREDERICK .'r, sNYnnn, on IiOSzrONMASSACHUsTTs f Y EYDROGENATION .orHYnRooAnBoNs ,AND1 Arlmitamns. rnnnnron .application area December 1e,1925,seria1'no.7g5,79s, ana ai Canaan/Laren e, 1925; neneweamy V5,1932'.` l

rlhis invention relates broadlylto the treating temperatures for theproduction ftherefrom of hydrocarbons of lower boiling tem- 1 5peratures, and the primary'object'of the invention is to 'produce thelower'borlingfrom retical amount based on the carbon content of 1o thehigher boiling material. n .c

dition of hydrogen to'themoleculesloffthef materials being treatedn Ingeneral, themagf terial isk vaporizedata low temperature, well below itstemperature of cracking or decomposition, by evaporatingv the materialinto a relatively large volume of gas consisting mostly of freehydrogen.

95. After evaporation, the mixture oftthevapor of the material andthehydrogen gas isf raised to a temperature at ,which hydrogen is absorbedinto the molecules of the material, and at which decomposition ofthe`molecules occurs with :formation ofy a'greater `number ofmolecules,'the.majority of'which will constitute material of lowerboiling temperature, such increased temperature bei-ng neverthelessbelow theA cracking temperature of the Y produced lower boilingmaterial. In other words, upon heating the material in. presence ofhydrogen, the 4molecules of the material are cracked and form a largernumber of,

molecules, most of which have bythe addi- 4o drogen than the originalmolecules. These new high hydrogen molecules form materialswith lowerboiling temperatures than the.

originall material.` ABy controlling the tem- 45 tion of'hydrogenahigher proportionof hyperatur'e, the .composition of the newly'`formed-molecules my be regulated toa con-'V1 :j i

siderable extent andfgin 'thisway,V the nature o f theproductlmay begovernedi The relatively f large volume Vof gas used .ensures anVeicient rate Yof operation and, what isiofao greater importance,ensures afsuihcientfreduci the higher boiling material easily,.inexpen-Y sively and in as nearly* as possible the-theof tion in the vpartialpressures oftheI original: material tovenable evaporation'below thede-n` composition temperature lthereof.r The increase in `fthe number of1 molecules, resulting 55 from heating and hydrogenation, increases rthe partial pressures sufficiently forsepara-L tion of the `producedmaterial from the gastol be easily eected by condensation at :tem-Tperatures which-caribe readilfyiand inexpemV 60h sively maintained' on-`a `commercial scale.` Y

The accompanying diagrammaticdi'avvinglv y i illustrates ,one'arrangement of jequipmentf` suitableffor carrying this process intoeect.

The material t0 be treated enters thewfapor-y G5A Y izerfll through`a'pipei12 controlled fbyfaf Valve 13,-'and is sprayedby afnoZZleiorsprinkler 14 over a filling'15,'fwhichconsists of refractoryringslor othermaterial not? af- ;y

ectedbythematerial being treated. rThis m,

llingis Vcontained'inagas-tight shell 16'andi-.

kisfsupporjced byascreen 17., Hot `zgas, fhighw in free hydrogen, entersthis'shell below=the 1 screen through `a-ppe :18"and passesup.:

through the filling 15 and in contact'with the H75.;

material from the nozzle 14, lowingdovvn"y over the surfaces oftheiilling 15. Thezvbl-:f ume; and :temperature of thei gas is'such thatmostof the liquid is evaporatedas itflows down in contact' with the gas.Any' materialisof` not evaporated collects ina reservoir `19 in the baseof' Vthe shell 16 and Acan be removedV through a pipe20v controlled" bya `valve 21.KV

. The mixture of hydrogen gas andthe vaporf of the evaporated vmaterialpassesl from thefs vaporizer 11, through a pipe 22 'tof hydrogenator 23,consisting of a shell 24econtainin=g tubes 25. These tubes are hea-tedon the*y out-Q side by gassuppl-iedthrough a pipe26`andburned withairfrom a blower 27. `The hety 90,/

products of combustion are circulated around the tubes and removedeventually through a pipe 28. The mixture of hydrogen and vapor passesVdown inside the tubes and is heated above the temperature at which someof the hydrogen is absorbed by the molecules vof Vthe vapor.V Any vaporwhich may vcomdense in the vaporizer is collected as liquid inareservoir 29 in the base of the vaporizer 23 and can be removed througha p ipe 30 lcontrolled by a valve 31.

The mixture of hydrogenatedvaporv and hydrogen gas passes from thehydrogenator 23 through a pipe 32 into the base of a heat exchanger 33.The hot mixture passes up-, wardly rinside the tubes 34 ofthe heat vex-Vchanger and is partially cooledby cool gas y which the mixture isfurther cooled by pass ing throughtubes 40 surrounded by water,

which isintroduced cold throughapipe 41 f Y and removed,'when heated,through a pipe,l 42.

In'this condenser,the cooling of the mixture changes mostof thevapor toliquid, which condenses in the tubes and runs down into a reservoiry 43.in the base of the condenser 39,

from which this portionA can beV removed by means ofa pipe 44,controlled byV a valve x45."

` Y. system. Regulation of gas discharge may be effectedbymeans of avalve50=inthelpipe 26,1V

Thecooled gasvremaining after 4the condensation of the vapor passes'from the con'- denser 39athrough a pipe-46. This gas'separates .intotwo'fportions. One portion goes through the pipe 26 and is used as fuelto heat thehydrogenator 23.- The other portion is pulled through anexhauster `blower 47 andY sent forward through a pipe48 to act as the 1cooling gasin the exchanger 33. f The gas re-V movedfrom the circulationthrough the pipe 26 is made up by fresh yhydrogen gas added .f to thevcirculation'through pipev 49. 'By this removal and addition,`theimpurities of the l hydrogen gas are prevented from accumulating in thesystem and lowering the concentration of .the hydrogen, which isrnormally kept ,above'95%'V by volume, but which may be as l low as 50%.

This operation can be carried on with the hydrogen gas under highvpres-Sura/(for example lbs. per square inch) so that the concentrationof thevhydrogen with reference to the vapor will 'be increased Y and'lthespeedof theV hydrogenation greatly increased. It will be understood, however,

that pressuresmay be used down to atmos-KY pheric or as much above 100pounds as practicable' commercially and safely: The amount' f from theof hydrogen present with the vapor in any case much greater than thatrequired for complete hydrogenation of the vapor. Any suitable means forcontrolling flow of gas'V through the pipe 26, such as a valve 52, willserve to retainvpressure in the apparatus.

Passing the cool gas around the tubes of the heat exchanger heats thegas and this heated Ygas passes'from the exchanger through the ingpartial pressure of the vapor of the mag-K- terial `being treated issolow that the resulting temperature of vaporization is below thetemperature at which thek material decomposes. In practice of thisinvention, the

.volume .of hydrogen gasis neXCe/ssof three times the amount required toprevent decomposition in the vaporizer,"and therefore manytlmeskthelvolume of vapor produced material, usually in excess of fiftytimes. n'

v'The supply of fresh gas to thecirculation contains enough hydrogen toreplace thatl absorbed and that burned or discharged from the system. Ifany permanent gas is evolved'V A yfrom the material being'cracked, thedischarge of gas must be correspondingly increased to maintain theamount in rcirculation approxi-V mately constant. Any such dischargemust 'Y be accompanied by compensating Vhydrogen.`

supply tolmaintain `the composition of the gas approximately constant. jAny material increase inthe amount of gas lin circulation would bebeneficial as regards evaporation, butwouldupset the thermal balanceofthe while the temperature in the evaporator may be controlled partlyby a'valve'l'regulating the admission of warm'gas thereto and partly byregulating the admissionfof air to the com# bustion in the heater 23. Ifdesired, the waste gas leaving through the flue-28 may be passed througha stove to preheat the air supplied to the heater 23. 1i v f v Ashydrogen is absorbed in the hydrogenator by the molecules of'highboiling temperature, there results'from the 'combined effects ofhydrogenation and heating several molecules of lower boiling temperatureforeach molecule hydrogenated. This represents a correspondingincrease-inthe lvolume of the vapor and an equivalent increase in thepartial pressure of the vapor. Any unhydrogenated vapor, condensing outdue tov this increase of the partial vpressure of the vapor,

is caughtin the reservoir 29 of the hydrogenator 23 and 'may be returnedfor retreat-` ment throughnpipe 12 to the vaporinzer 11.

-This increase of partial vvapor pressure also improves condensingconditions in the connumber of molecules duejto hydrogenation andcracking, the very-low partialpressure of the original vapor wouldnecessitate a very low condensing temperature, probably sub- Zero, butby reasonof the increased number of molecules.and increasedpartialpressure of thepr'oduced'low boiling material the desiredcondensation maylbeetl'ec'ted at temperatures easily and cheaplymaintainedin commercial operations. l

The liquid that condenses in the reservoir 3,5 of the exchanger 38 isusually still toohigh in boiling temperature for retention as a finalproduct, and may be subjected to reevaporation andl furtherhydrogenation.`

A convenient way to obtain the gas of high hydrogen content used in thisprocess is by cracking naturali gas at a high temperature andremovingthe resultingfree carbon.

.Purposely, the process has not been heretofore identified with thetreatment of any particular material, for the reason that a greatvariety ,of materialsmay be treated along the lines indicated with7perhaps, modiiicationsv or additions peculiar to the material.

Crude petroleum, either asphalt or paratn base, may betreatedsubstantiallyas described for the production of gasoline andother normally liquid or readily liqueiiable hydrocarbons may besimilarly treated. For the treatment of other materials, such asbituminous sand, oil shale, bark, sawdust, garbage, peat, lignite oreven coal, which are normally'solid, suitable means must be provided forhandling the material in the evaporating step, with, of course, theemployment in 4this step of vtemperatures and pressures suitable for thematerial. Since temperature, pressure and relative volume of hydrogenmost suitableA for any given material can be determined only byexamination of the material, these details have been stated only ingeneral terms applicable to any vand all classes of material susceptibleof treatment according to this invention, and it will therefore beunderstood that the invention is notl limited to any precisetemperature, pressure or relative amount of' hydrogen. 'a

Having `hus described my invention, what I claim is l. A process 0Iproducing low boiling hydrocarbons from higher boiling hydrocarbons,including'the steps of heating and evaporating the higher boilinghydrocarbons by yContact with gas heated to 'a t-emperature below thecracking temperature of said higher boiling hydrocarbons, the volume ofsaid gas being such that it will constitute over 90 per cent of thevolumeof the gas and vapour mixture that will be produced by evaporationof said higher boiling hydrocarbone into said gas, the gas containing inexcess of fifty per cent of free hydrogen by volume; `and crackingsaidvapours by heating the gas and vapours toa temperature above ithecracking temperature j of i saidQva-j pours while maintaining apressure between atmosphericpressure and approxi hundredpounds persquare inch.v

2. A process oit' producing low boiling-hydrocarbons Vfrom .higherboiling hydrocarbons, `including the steps of heatingnand evaporatingvthe 4.higher boiling hydrocarbonsby contact Awith gas (heatedtoaltempe'rature below the Vcracking temperature 'of ately elle..

the 'said higherboiling hydrocarbms,said

gas containing a volume of Vfree .hydrogen in excess of five times thevolumev of theva-l `pours `that willbe present inl` the mixture producedby evaporation` of said 'higher boiling hydrocarbons into said gas.

3. process.` of producing hydrocarbon oil of higher boiling points,which comprises vaporizing theloilof higher boiling point Aby iilmingitand contacting it with a gas preheatedto a ,temperature gasoline frombelow the cracking tenipjerature ofithef oil,

removinggsaid gas and-thevapours subsequently `cracking said vapours `byheating said gas and vapours to. a temperature above a pressurebetweenatmospheric-,and approximately 10() pounds per s uare inch,l"said gas containing a volume'o free ,hydrogen of between Iive andiftytimesfthe volume of hydrocarbon 'vapou'rin the mixturefpasslng fromthe 'vaporization 'step and l'causing a part of said hydrogen to combinewithsaidf cracked vapour, then cooling said gasV andV and the admixedoilvapoursand su'bequent-` ly cracking the foil vapours by heating thegas ,and oil vapours to a temperature above the cracking temperaturefofthe oil vapours 'e at apressure between atmospheric' pressure andapproximatelylOO pounds per square inch, said gas containing a'vo'lumeAof free hydrogeny of betweenvlive and Efifty times the volume ofhydrocarbon vapour in the mxtifepassieg from thewporizaan l step andcausingV apart of said `hydrogen to combine with said crackedvapour,then``c'ool ing said vgas and the'vapour resulting from suchcracking and hydrogen'absorption to condense the gasoline'-formed,fafterfirstiremoving the vapour of uncracked oil by partial cooling,andsubsequently renewing YVthe hydrogen proportionof said gas andre-using.

said gas to vaporize additional oil.,`

y 5. A process of producing low boilinghydrocarbons .from higher boiling.hydrocar- 9-0 the cracking temperature of the vapoursfat bonsV in YwhichV process the boiling 'hydrocarbonsare heated andevaporated at alow partial pressure by contact'f'withjgas heated to at'emperaturelbelow the cracking temperature of said highfboiling4hydrocarbons',y said gas containing in excess .of five volumes offfreehydrogenfor each volume of highboiling hydrocarbon vapour in the gas iand vapour mixture resulting frointhe evap- 1o oratio'n, increasing thepartial pressure'partly by reducing the average molecular weight o-saidlvapour by cracking said vapour by heatinglthe gas'and high boilingvapour to Y i a temperature abovefthe cracking temperature'ot the highboiling vapour while maintaining a pressure between atmospheric pressureand approximately 100 y pounds per square inch, the aforesaidl increaseof partial pressure being effected' partly by reducing the'voluine ofsaid gas by causinghydrogen to combine with the vapourv and subsequentlysol phericpressure, increasing thepartial pres-` sure of said vapour andreducing the partial pressure of the hydrogen by causing saidy vapour tocrack andi absorb hydrogen by heatf' ing said gasVand-vapour Atoatemperature abo-vethe cracking temperature of thevapour-*while'maintaining a pressureV between vatmospheric pressure andapproximate-151100 pounds-per square inch and condensing` the resultinghydrocarbon vapoursf at such Vincreased'partial-pressure'by coolingfsaidgas and admixed vapours. i

f7. A process of producing low boiling-hydrocarbonsfrom higher boilinghydrocarbons, which comprises evaporating said higher boilinghydrocarbonsat a temperature be- .low'the decomposition temperature ofsaid hydrocarbons by contact with gas heated to a temperature below thedecompositionv teinperature'of the hydrocarbons',Y said gas containingreehydrogen at al partial Vpressure above ninel pounds absolute, Vpersquare inch, andV the partial pressurel of said hydrocarbons as vapourin said gas being less than live poundsk absolute per squareinch,cracking' said vapour'by heating the vapour and gas above the cracking'temperature ofy said vapour while maintaining a pressure betweenatmosphericrpressure andlapproxiniately 100 poundsV per square inch andVcondensing the hydrocarbon products ofy lthecrackingfby cooling'said gasand the vapours therein..

8. A process of making low boilinghydro- Y carbons from higher boilinghydrocarbons, which comprises evaporating .the higher boilinghydrocarbons by contact with jgas heated to a temperature belowthelcralcking temperature of said high boilinghydrocarbons,y the volumeofsaid gas being such l.that it will constitute over ninety per cent ofthe volume oirthegas and vapour mixture resulting from the evaporationof said higher boiling'hydrocarbons l,into said gas, the gascontainingin excess of fifty percentv of iree hydrogen .by volume, andcracking said vapours by heating the gas and vapours toa temperatureabove the cracking temperature of said .,vapours while maintaining"super-atmospheric pressure, and cooling the gas and contained vaporou'scrackingl products suiiiciently to condense the vaporous crackingproducts.V

'9. Aprocess of producing lo-w boiling hydrocarbons from higher boilinghydrocarbons,k including the steps .of heating and evaporating the.higher boiling hydrocar-Vv bons by contact with gasheated to a teinperlature belowthe cracking'temperature oi the said 'higher boilinghydrocarbons, said gas containing a volume of free. hydrogen in excessof'ive timesr the volume of the vapours that will be present in themixture produced by evaporation of said higher boiling hydrocarbonsintosaid gas7 and cracking the hydrocarbon vapour in contact withsaid gas byheating the gas and vapour mixture to a teinperature above the crackingtemperature of the hydrocarbon vapours and below the `crackingtemperature of the lighter vapours which it is desired to produce; 1

`lvO.gAV process of: obtaining hydrocarbons of' low yboiling.pointsfroinhydrocarbons of high boiling points, which comprises'heating saidhydrocarbons or high .boiling points by contact with hot gas, thetemperature of said gas being below thecracking temperature of 1 l Y tnehydrocarbonsvoi: highest boilingY points contained in said hydrocarbonsci high boiling points and rthe vvolume of s aid ygas being such that atthe temperature oi' the gas the hydrocarbons ofliighboiling points willeval veov crate into the gas as hydrocarbon vapor during Y said Contact,the contents of the gas in 'free hydrogen being greater than theA amountof hydrogen required for the VformationV of hydrocarbonsoi low boilingpoints from the hy-` drocarbons of high boiling' points;` subseqnentlyto said evaporation raising the temperature of thevapor and the gas to adegree at which the `molecules of hydrocarbons of high .boiling point inthe vapor will divide.

with the absorption otpart of the free hydrogen of the gas and theformation of hydrobeing below the cracking temperature of the carbons oflow boiling points, the temperature l`to which said gasifandv vapor is`raised formed hydrocarbons of low boiling points; subsequently removingany untransformed hydrocarbons of high boiling points from the gas bycooling the gas tol a temperature at. which the vapor of anyuntransformed hydrocarbons condense while the major portion of thevapors of the hydrocarbons of low boiling points remain in the gas; andsubsequently further cooling the gas to condense from the gas thehydrocarbons of low boiling points, then removing from the uncondensedgas a volume of gas such that the hydrogen in said removed gas added tothe hydrogen absorbed is in the same ratio to the sum of said removedgas and said absorbed hydrogen as the hydrogen in the gas used for saidevaporation is to the total of saidgas.

11. An apparatus for the hydrogenation of hydrocarbons which'includes avaporizer having means to distribute the hydrocarbon in a thin film andto direct hot gases into contact with the lmed hydrocarbon, a heatexchanger, a condenser, a hydrogenator, connections between thevaporizer, heat exchanger, condenser and hydrogenator for circulatinggas through the heat exchanger, vaporizer and hydrogenator and againthrough the heat exchanger following a path isolated from the first,through the condenser and back to the heat exchanger and hydrogenator,means for introducing hydrogen into the circulation and means forremoving gas vfrom the circulation and means for heating the materialpassing through the hydrogenator.

12. An apparatus for the hydrogenation of hydrocarbons which includes avaporizer having means to distribute the hydrocarbon in a thin film andto direct hot gases into contact with the filmed hydrocarbon, a heatexchanger, a condenser, a hydrogenator, connecpartially cooled gas andVapour therefrom In witness whereof, I have hereunto set hand. Y

FREDERICK T. SNYDER.

tions between the vaporizer, heat exchanger,` 'l

condenser and hydrogenator for circulating gas through the heatexchanger, vaporizer and hydrogenator and again through the heatexchanger following a path isolated from the first, through thecondenser and back to the heat exchanger, and means for heating materialpassing through the hydrogenator, means for withdrawing gas from thecirculation for fuel in said heating means, and means for introducinghydrogen into the circulation.

13. Apparatus for hydrogenation of hydrocarbons which includes avaporizer, means for introducing a hydrocarbon into said vaporizer,means for passing hot gas through the vaporizer in contact with thehydrocarbon therein to vaporize the hydrocarbon into said gas, ahydrogenator connected to the Vaporizer to receive gas and vapourtherefrom, means to heat the hydrogenator, a heat exchanger connected tothe hydrogenator toreceive hot gas and vapour therefrom and to heat gasflowing to the vaporizfer, and a condenser connected to the heatexchanger to receive

